Electric translating apparatus



y 23, 1940- G. w. GARMAN 2,202,732

' ELECTRIC TRANSLATING APPARATUS Original Filed April 24, 1937 R A inventor:

V \f f George W.6r-man, l/ L/ b3,/R WJM-ZM1 Us Attorney.

Patented May 28, 1940 UNITED STATES ELECTRIC TRANSLATING APPARATUS George W. Garman, Scotia, N. Y., assignor to General Electric Company, a corporation of New York Application April 24, 1937, Serial No. 138,817 Renewed October 10, 1939 12 Claims.

My invention relates to electric translating apparatus and more particularly to electric valve circuits.

In the control of electric valve apparatus, par- 5 ticularly in the control of electric valve apparatus of the type employing an ionizable medium such as a gas or a vapor, it is frequently desirable to furnish voltages of perpendicular wave front to control the electric valve apparatus. By impressing voltages of perpendicular wave front on the control members of electric valves, it is possible to effect precise and positive control of electric valve means. Furthermore, it is important to control electric circuits by electric valve apparatus to effect energization of an associated load circuit during a predetermined interval of time and to control the amount of energy trans mitted during the interval. Heretofore to accomplish these results it has been necessary to employ complicated apparatus of inordinate proportions relative to the size and rating of the equipment to be controlled. In view of these factors, there has been evidenced a decided need for control apparatus for performing these func- 36 tions which is simple in construction and arrangement and which is susceptible of great flexibility and precision of control.

It is an object of my invention to provide a new and improved control circuit.

It is another object of my invention to provide a new and improved electric valve circuit.

It is a further object of my inventionto provide a new and improved control system for electric valve translating apparatus.

In accordance with the illustrated embodiment of my invention, I provide a new and improved control circuit for electric valve apparatus. The control circuit includes an arrangement for controlling the transfer of energy between circuits whereby the period of energization and the amount of energy transfer during the period may be accurately and precisely controlled. Electric valvcs having control members are used to effect this control and the control 51 circuit includes an inductive device, such as a transformer, and a pair of electric circuits for energizing the transformer to induce in the secondary winding thereof an alternating voltage which impresses suitable alternating voltages on 5 the control members of the electric valves. A pair of electric valves is connected in the circuits to control the phase relation and the wave form of the alternating voltage impressed on the control members, and other electric valve means is employed to control the period of energization of LSU the control members and thereby to effect control of the period of energy transfer.

For a better understanding of my invention, reference may be had to the following description taken in connection with the accompanying drawing, and its scope will be pointed out in the appended claims. Fig. 1 of the accompanying drawing diagrammatically shows an embodiment of my invention as applied to an electric valve translating circuit for effecting periodic energization of an associated load circuit and Figs. 2 and 3 represent certain operating characteristics thereof.

Referring to Fig. 1 of the drawing, my invention is diagrammatically shown as applied to an electric valve translating circuit for transmitting energy from an alternating current supply circuit l to a load circuit, such as a welding circuit 2, through a transformer 3. A suitable circuit controlling means such as an inductive device or transformer 4 having a primary winding 5 and a secondary winding 6 may be connected in series relation with the circuit I and the transformer 3 to control the amount of energy transmitted to the welding circuit 2. A pair of electric Valves l and 3, which may be connected reversely in parallel, are connected across the secondary winding 6 of transformer 4 to control the effective impedance of the primary winding 5, thereby effecting control of the amount of energy transmitted to the welding circuit 2 from the supply circuit I. Each of the electric valves 1 and 8 includes an anode 9, a cathode NJ and a control member H and are preferably of the type employing an ionizable medium such as a gas or a vapor.

To control the conductivities of the electric valves 1 and 8 to render these valves conductive for a predetermined interval of time and to control the amount of energy transmitted to the v welding circuit 2 from the supply circuit I during the interval of time, I provide a circuit i2 including a source of alternating current 13, a suitable inductive device, such as a transformer it having a primary winding l5 with an electrically intermediate connection l6 and secondary windings l! and I8, and a transformer 19 having a primary winding 20 and secondary windings 2| and 22. While in the arrangement diagrammatically shown in Fig. 1 the circuit I2 is shown as being energized from an alternating current circuit l3, it is to be understood that I may employ any source of alternating current properly correlated in phase and frequency relative to the voltage of the alternating current circuit l, and that I may connect the circuit E2 to circuit 5 if desired. The circuit l2 includes an electric valve 23, liav" ing an anode 2 5, a cathode and control mem bers 26 and ill, which is preferably of the type employing an ionizable medium such as a gas or a vapor and which controls the eriod of energization of the welding circuit the alternating current circuit i. Cathod' of electric valve 23 is connected to the elec ."ically mediate connection it of primary winding of transformer M. Electric valve means til and are associated with secondary windings 2i and respectively, of transformer 69. Each of the electric valves 23 and is provided with an anode 36], a cathode and a control The cathodes M of these electric valves are )l1- nected to anode of electric valve through a conductor Secondary windings 2i and of transformer it are also connected to primary winding it of transformer it through conductors and 35, respectively. Secondary windings ill and 22 taken in connection. with the associated electric valves 283 and and the common electric valve 23 constitute a pair of electric circuits which alternately energize primary winding iii of transformer it in opposite directions to induce in the secondary windings ll and iii of trans-- former M alternating voltages of predetermined duration and predetermined wave form. Electric valves 2% and 2% also serve to control the time during the respective half cycles of applied voltage at which the circuits initiate the co duction of current through the primary winding it of transformer Resistances are ccnnected across secondary windings ii and it or transformer M and serve to impose a predomt nantly resistive load on these secondary windings, and current limiting resistances are employed to control the current supplied. to the control members ii of electric valves l and Suitable sources of negative unidirectional biasing potential, such as batteries 38, are connected in circuit with control members it of electric valves and 8.

To control the time during each positive half cycle of voltage applied to electric valves 28 and 29 at which these valves are rendered conductive, I employ a suitable circuit such as an impedance phase shifting circuit including an inductive device dB for providing an alternating voltage and a voltage of intermediate value, an adjustable resistance ll, a capacitance 412 and a transformer Current limiting resistances M are connected in series relation with the output circuit of the transformer id. The phase shifting circuit 39, acting in conjunction with electric valves 28 and 2d, serves as an agency for controlling the amount of energy transferred to the welding circuit 2 from the alternating current circuit i. This control is effected by controlling the phase positions of the voltages impressed on control members ll of electric valves 1 and 8 by secondary windings ii and ill of transformer i l relative to the alternating voltages impressed on anodes 8 of electric valves l and 53 by secondary winding 6 of transformer :2. Fur thermore, by retarding the phase of the voltages impressed on control members 32 of electric valves 28 and 29, the alternating voltages impressed on control members ll of electric valves 7 and 53 are of perpendicular wave front to effect precise control of electric valves '1 and 8. By the adjustment of the resistance M, the phase of the alternating voltage impressed on control members 32 of electric valves 28 and 29 may be controlled relative to the voltage impressed on the associated anodes 30. Although the phase shifting circuit 39 is shown as being connected to the alternating current circuit I3, it is to be understood that the circuit 353 may be connected to the circuit I or to any other suitable source of al-- ternating current correlated in phase and frequency relative to the voltage of circuit I.

I employ a suitable timing circuit 65 for providing a periodic voltage for energizing control member 21 of electric valve 23 to render this valve conductive periodically. Control member 26 of electric valve 23 may be connected to cathode 25 or to any potential less positive than that of anode 24. The circuit 45 may comprise a source of unidirectional potential 36, a voltage divider including a resistance ll having adjustable taps 48 and 69, a capacitance 58 which is charged from source 16 through an adjustable resistance 56 and an electric valve 5H for periodlcally discharging the capacitance 50. Electric valve 5! includes an anode 52, a cathode 53 and a control member 53', and is preferably of the type employing an ionizable medium such as a gas or a vapor. series with electric valve 5! to assist in periodically rendering the valve nonconductive and a suitable circuit controlling means such as a switch 55 may be connected in circuit 15. A circuit including any conventional phase shifting arrangement, such as a rotary phase shifter 56 and a transformer 51, may be used to render electric valve 51 conductive at the proper predetermined times to effect the desired correlation with the voltages of circuits l and i3. Transformer cl may be of the type designed to furnish an alter-- hating voltage of peaked wave form.

Although circuit i2 is shown as comprising a part of a control system for other electric valve apparatus, it is to be understood that my invention in its broader aspects may be employed as an electric valve translating circuit where it is desired to effect energization of an associated load circuit which could be connected to secondary windings H or I8 of transformer M. Further more, it is to be understood that it may be desirable to employ only one of the circuits of circuit H! to supply only unidirectional impulses of voltage to a load circuit and to control the amount of energy transmitted to the load circuit. This result may be effected by employing only one of the controlled rectifiers, such as electric valve 28, electric valve 23 and the associated secondary winding 2! of transformer H] to induce trains of unidirectional periodic impulses in secondary windings I! and I8, each train including a predetermined number of voltage impulses.

The operation of the embodiment of my invention diagrammatically shown in Fig. 1 of the accompanying drawing will be explained when the arrangement thereof is effecting periodic energization of the welding circuit 2 from the sup ply circuit I through transformers 3 and i. Circuit l2 controls the alternating voltages impressed on control members H of electric valves l and ii so that these valves control the impedance oi. primary winding 5 of transformer 4 to control the energy supplied to welding circuit 2. The length of the periods of energization of the welding circuit 2 and the periodicity of such energizetions are controlled by electric valve 23 and timing circuit 45, and the amount of energy transmitted during the periods is controlled by electric valves 28 and 29 and phase shifting circuit 39. Electric valves 28 and 29 and phase shifting cir- An inductance 54 is connected in cuit 39 control the amount of energy transmitted to circuit 2 from circuit l by controlling the phase of the voltages impressed on control members H of electric valves 1 and 8 relative to the alternating voltages impressed on the associated anodes 9.

Considering now more particularly the operation of the individual circuits of the system, it will be understood that when the voltages impressed on control members ll of electric valves 1 and 8 are in phase with the voltages impressed on the associated anodes, the impedance of primary winding of transformer 4 will be mini mum, and when there is substantial phase oppo sition between these voltages the impedance of winding 5 will be maximum. For intermediate phase relationships, the impedance of winding 5 will assume corresponding values. In this manner, the energization of welding circuit 2 is controlled.

Circuit l2, by virtue of the two circuits including secondary windings 2| and 22, electric valves 28 and 29 and electric valve 23, energizes transformer I4 to induce alternating voltages variable in phase and of controllable Wave form in secondary windings I1 and IS. The two circuits conduct current alternately to energize primary winding l5 of transformer I4 in opposite directions to induce in secondary windings I! and I8 the desired alternating voltages. For example, during a half cycle of voltage of one polarity the upper half of primary winding l5 of transformer M will be energized through a circuit including secondary winding 2! of transformer l9, and electric valves 28 and 23. During the next half cycle of opposite polarity, the lower half of primary winding IE will be energized through a circuit including secondary winding 22 of transformer l9, and electric valves 29 and 23. Since these energizations of primary winding I5 are in opposite directions, alternating voltages will be induced in secondary windings l1 and [8.

The period of energization of transformer I4 and the interval between the periods of energization are controlled by electric valve 23 and the timing circuit 45. Circuit 45 generates a periodic voltage, the period of which may be controlled by adjusting resistance 50, and the ratio of timeon to time-off may be controlled by adjusting tap 48 of resistance 41. The periodic voltage furnished by timing circuit 45 is impressed on control member 21 to render electric valve 23 periodically conductive.

The operation of the illustrated embodiment of my invention will be better understood by considering the operating characteristics shown in Fig. 2. The curves of Fig. 2 may represent the rectified alternating voltage impressed on electric valve 23 by secondary windings 2| and 22 and electric valves 23 and 29 during one period of energization corresponding to two cycles of voltage of circuit 5. By adjusting phase shifting circuit 39, electric valves 28 and 29 may be rendered conductive at approximately the maximum values of the impressed voltage as represented by points a, b, c and cl, so that electric valve 23 conducts current during the intervals represented by the solid curves A, B, C and D. During the intervals represented by the broken curves, no current is transmitted. This train of voltage impulses ire-- pressed on primary winding !5 of transformer 54 induces in secondary windings l7 and E8 alternating voltages having a wave form as represented by curve E of 3. By controlling the voltage impressed on primary winding IS, the

amount of energy transmitted to the secondary windings I"! and I8 is controlled, and the amount of energy transmitted to welding circuit 2 from supply circuit 1 is also controlled. The maximum consecutive number of half cycles of voltage in each train induced in secondary windings ll and I8 is controlled by electric valve 23. The non conducting intervals, as represented by the broken curves, afford an interval in which the control member 2'! of electric valve 23 may gain control.

While I have shown and described my invention as applied to a particular system of connections and as embodying various devices diagram matically shown, it will be obvious to those skilled in the art that changes and modifications may be made without departing from my invention, and I, therefore, aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent in the United States is:

1. In combination, an alternating current circuit, a second alternating current circuit, electric translating apparatus interconnecting said alternating current circuits and including a pair of electric circuits arranged to conduct current alternately to transmitenergy from said first mentioned circuit to said second circuit, a pair of electric valves each having a control member and each connected in a different one of said pair of circuits, an electric valve means connected in series relation with said pair of electric valves to control the period during which energy is transmitted by said pair of circuits, and means for energizing said control members to control the amount of energy transmitted by said pair of circuits during said period.

2. In combination, an alternating current sup ply circuit, a second circuit, and electric trans lating apparatus interconnecting said circuits comprising an inductive device having a primary winding and a secondary winding connected to said second circuit, a pair of electric circuits connected to said primary winding for transmitting current alternately and arranged to induce an alternating voltage in said secondary winding, a pair of controlled rectifiers each connected in a difierent one of said pair of circuits to control the part of each half cycle of the voltage of said, supply circuit during which said pair of circuits transmit current and an electric valve means connected in. series relation with said pair of controlled rectifiers to control. the period of energization of said second circuit.

3. In combination, an alternating current supply circuit, a second circuit, and electric translating apparatus interconnecting said circuits comprising a transformer having a primary winding and a secondary winding connected to said second circuit, a pair of electric circuits energized from said supply circuit and being connected to said primary Winding, said pair of electric circuits being arranged to conduct current alternately an each including an electric valve for controlling the time during each positive half cycle of impressed voltage at which current conduction is initiated, and an electric valve connected in said pair of of circuits for controlling the number of consecutive half cycles of voltage induced in said secondary winding.

4. In combination, an alternating current supply circuit, a second circuit, a transformer having a primary winding and a secondary winding connected to said second circuit, and means for Cir energizing said primary winding to induce in said secondary winding an alternating voltage of perpendicular wave front including a pair of electric circuits energized irom said supply circuit and arranged. to energize said primary winding alternately in opposite directions, a pair of electric valves each connected in a different one of said pair of circuits and each. having an anode, a cathode and a control member for controlling the conductivity thereof, a circuit for impressing on the control members control voltage to render the electric valves conductive within the region of the maximum value of impressed anode volt- We. and an electric valve connected in series relation with said p ol. electric valves to con trol the number of half cycles of voltage impressed on said second circuit.

5. In combination, an alternating current supply circuit, a second circuit, a transformer having primary winding and a secondary winding connected to the second circuit, a pair of circuits interposed between. supply circuit and said primary winding, pair of electric valves each connected in a different one of said pair of circuits nged to conduct current alternately to ze said primary windin in opposite directions to induce an. alternating voltage in said secondary winding, means for controlling said pair of electric valves to impress on said primary winding an alternating voltage of perpendicular wave front, an electric valve connected in series relation with said pair of electric valves, and a circuit for supplying a periodic timing quantity to render said last mentioned electric valve conductive for a predetermined time to effect energization of said second circuit for a corresponding interval of time.

6. In an excitation circuit for an electric valve means having a control member, the combination of a source of alternating current, a transformer having a primary winding and a secondary winding connected to said control member, a pair of electric circuits interposed between said source and said primary winding and arranged to conduct current alternately to energize said primary winding in opposite directions to induce an alternating voltage in said secondary winding, an electric valve connected in said pair of circuits to control the period of energization of said primary winding and a pair of controlled rectifiers each "connected in a dilrerent one of the pair of electric circuits for controlling the wave shape of the alternating voltage induced in said secondary winding.

7. In combination, an alternating current supply circuit, a second circuit, electric translating apparatus interconnecting said circuits and including a pair of electric circuits arranged to conduct current alternatively to transmit energy from said supply circuit to said second circuit, a pair of electric valves each having a control member and each being connected in a difierent one of said pair of circuits, an electric valve means connected in series relation with said pair of electric valves to control the period during which said second circuit is energized, and means for impressing on the control members of said pair of electric valves alternating voltages variable in phase relative to the voltage impressed across said electric valves to control the wave form, of the voltage impressed on said second circuit.

8. In combination, an alternating current supply circuit, a load circuit, an electric valve means interposed between said circuits for controlling the transfer of energy therebetween and being aaoarca provided with a control member for controlling the conductivity thereof, and an excitation circuit for energizing said control member including a source of alternating current, a transformer having a primary winding and a secondary winding connected to said control member, a pair of electric circuits interconnecting said source and said primary Winding, a pair of electric valves each connected in a different one of said pair of circuits and arranged to conduct alternately to energize said primary winding in opposite directions to induce an alternating voltage in said secondary winding, an electric valve connected in series relation with said pair of electric valves to control the period of energization of said control member and means for controlling said pair of electric valves to control the amount of energy transmitted from said supply circuit to said load circuit during said period of energization.

9. In combination, an alternating current supply circuit, a load circuit, an electric valve means interposed between said circuits for controlling the transfer of energy therebetween and being provided with a control member for controlling the conductivity thereof, and an excitation circuit for energizing said control member including a source of alternating current, a transformer having a primary winding and a secondary Winding connected to said control member, a pair of electric circuits interconnecting said source and said primary winding, a pair of electric valves each connected in a diiferent one of said pair of circuits and arranged to conduct alternately to energize said primary winding in opposite directions to induce an alternating voltage in said secondary winding, an electric valve connected in series relation with said pair of electric valves to control the maximum consecutive number of half cycles of voltage impressed on said control member, and means for controlling the conductivities of said pair of electric valves to control the phase relation of the voltage impressed on said control member relative to the voltage of said supply circuit to control the current supplied to said load circuit.

10. In combination, an alternating current supply circuit, a load circuit, an electric valve means interposed between said circuits for controlling the transfer of energy therebetween and being provided with a control member for controlling the conductivity thereof, and an excitation circuit for energizing said control member including a source of alternating current, a transformer having a primary winding and a secondary winding connected to said control member, a pair of electric circuits interconnecting said source and said primary winding, a pair of electric valves each connected in a different one of said pair of circuits and arranged to conduct alternately to energize said primary Winding in opposite directions to induce an alternating voltage in said secondary winding, means for controlling said pair of electric valves to control the wave form of the voltage impressed on said control member and an electric valve connected in series relation with said pair of electric valves to control the maximum consecutive number of half cycles of voltage impressed on said control member.

11. In combination, an alternating current supply circuit, a load circuit, electric valve means interposed between said circuits, said electric valve means having a control member for controlling the conductivity thereof, and an excitation circuit for impressing on said control member trains of periodic voltage impulses comprising a source of alternating current, an inductive device for energizing said control member, a" serially connected rectifier and an electric valve for energizing said inductive device from said source, means for controlling said second mentioned electric valve to render said valve conductive periodically and means for controlling the conductivity of said rectifier to control the phase of the voltage impulses relative to the voltage impressed across said electric valve means to control the energy transmitted to said load circuit.

12. In combination, an alternating current supply circuit, a load circuit, electric translating apparatus interconnecting said circuits and comprising a pair of electric circuits each including a rectifier, a unitary electric valve means connected in series relation with both rectifiers in said pair of circuits, said electric valve means having a control member for controlling the conductivity thereof, means for impressing on said control member a potential to render said electric valve means conductive for a predetermined number of consecutive half cycles of said supply circuit, and means for controlling the conductivity of the rectifiers to control the energy transmitted from said supply circuit to said load circuit during said half cycles.

GEORGE W. GARMAN. 

